The present invention relates generally to a magnetic tape cassette. More specifically, the invention relates to a tape cassette enclosing a magnetic tape wound onto tape reels and a reel brake which can be released by opening a tape-protecting lid.
It is well known that recording and reproduction of data, such as audio signals, is facilitated by utilizing a magnetic tape cassette and a recording and reproduction apparatus adapted for use with cassettes. It is also well known that by providing a reel brake mechanism, unintentional unwinding of the tape from the tape reels can be successfully prevented. In known structures, a reel brake is normally biased toward the tape reel to ensure braking engagement with the latter.
When such a tape cassette is loaded into the recording and reproduction apparatus, it is necessary to release the braking engagement between the reel brake and the tape reel. A brake release mechanism has been proposed which operates the reel brake mechanism via a tape-protecting lid which covers the front mouth of the tape cassette. In the proposed mechanism, the reel brake mechanism cooperates with the tape-protecting lid to be actuated between its braking state and its brake-release state. It should be noted that, throughout the disclosure, the wording "braking state" is used to represent the reel brake position in which rotation of the tape reels are restricted or prevented, and the wording "brake-release state" represents the reel brake position in which the reel brake is separated from the tape reel and so allows free rotation of the tape reels.
The known brake release mechanism cooperates with the tape protecting lid via a side plate of the latter. Specifically, in the known mechanism, the reel brake has a transversely extending strip which is positioned opposite the side plate of the tape-protecting lid. When the tape-protecting lid opens the front mouth of the tape cassette, the side plate pushes the strip of the reel brake in the brake-release direction to move the latter to the brake-release state.
In this structure, a deformed side plate could prevent cooperation between the reel brake and the tape-protecting lid. This prevents release of the reel brake upon opening the tape-protecting lid. Since the reel brake prevents the tape reels from rotating as set out above, recording and reproduction becomes impossible.